Strand processing



May 17, 1960 D. s. ADAMS ErAL STRAND PROCESSING 4 Sheets-Sheet 1 FiledSepfz. 10, 1954 INVENTOR DUSTIN S. ADAMS JOHN F. BOWLING ATTORNEY May17, 1960 o. s. ADAMS ETAL 2,9

s'rmun PROCESSING Filed Sept. 10, 1954 4 Sheets-Sheet 2 INVENTOR DUSTINS. A DAMS JOHN F. BOWLING BY g f ATTORNEY May 17, 1960 p, 's ADAMS ET AL2,936,877

STRAND PROCESSING Filed Sept. 10, 1954 4 Sheets-Sheet 3 FIG. 6

INVENTOR DUSTIN S. ADAM S JOHN F. BOWL|NG BY 9- OC ZM ATTORNEY May 17,1960 D. S. ADAMS Filed Sept. 10, 1954 STRAND PROCESSING 4 Shets-Sheet 4@WHII 9 3 INVENTOR DUSTIN S. ADAMS JOHN F. BOWLING ATTORNEY accompanyingdiagrams.

nite i STRAND PRocEssnvG I Dustin S. Adams, West Chester, Pa., and JohnF. Bowling, Wilmington, Del., assignors to E. I. du Pont de Nemours &Company, Wilmington, Del., a corporation of Delaware ApplicationSeptember 10, 1954, Serial No. 455,192 21 Claims. (Cl. 203-1) StatesPatent Patented May 17, 1960 about by imparting to a traveling strand ahelical configuration having an axis substantially parallel to theoriginal direction of travel. In an apparatus embodiment this isachieved by passing a rapidly traveling strand through a guide makingthe circuit of a plurality of sup porting elements adapted to receivethe strand and ad vance it in substantially helical form for depositiononto a collecting surface. The rate of travel of the guide with respectto fixed external coordinates is of the same order of. magnitude as therate of travel of the strand with respect. to the guide, and theresulting helical configuration of the strand on the supporting elementsmoves axially therealong at a speed that is exceeded greatly by theori.-

ginal strandtravel rate. The collecting surface receives the strandfrom. off the ends of the supporting elements at reduced speed in theform of coils or loops that adapt themselves readily to theconfiguration of the collecting surface; the collapsed configuration ofthe strand on the collecting surface may be controlled by movement ofthe collecting surface with respect to the apparatus, as

' well as by the relative spacing of the elements themselves.

Attempts to increase the operating speeds .of present 1 equipment leadto excessive wear and impose severe stress inequalities leading tounever dyeing and other nonuniformities in the product. Airjets haveproved helpful in drawing oil? or forwarding light-weight strands, butthe problem of collecting these and similar heavy strand materials incompact, orderly form for convenient backwinding or other use remains,

The present invention is directed toward the processing of all forms ofstrand material as here defined, The term strand herein meansmonofilament, multifilaments, tow, sliver, staple yarn, thread, ribbon,rope, and other articles capable of being handled as described,regardless of their composition, cross-sectional appearance, or methodof construction and despite exemplification by such textile material astow (a bundle of substantially continuous filaments).

object is tensioning of a strand so as to forward it against;

a restraining force. Another objecti-s controlled extension of atraveling strand. Other objects, including provision of means forattaining the above and related objects, will be apparent from theexplanatory text and the Figure 1 is a perspective view of one form ofapparatus useful according to this invention. Figure 2 is a plan view ofthe apparatus of Figure 1. Figure 3 is a vertical section of a portionof the same apparatus through the central axis at 3-3 of Figure 2'.Figure 4 is a vertical. section of a different portion of the sameapparatus. Figures 5 and 5A are fragmentary plan views of the apparatusof Figure 1 in conjunction with accessory apparatus. Figure 6 is asideelevation of another form of apparatus.

- I cylindrical rolls 5.

Thus, the strand is drawn off from the source of supply in a directionsubstantially in line with the axis of the helical configuration, andthe rapid rate of travel in that direction is converted to slowadvancement of the helical configuration therealong; while thelengthwise component (now in a direction substantially:perpendicular tothe original direction), if any, is greatly reduced and may be zero oreven negative as will appear below.

While being advanced in helical form, the strand may a be extended,heated, or otherwise treated as may be com venient and desirable,depending upon-its chemical and physicalcomposition and its desiredcharacteristics and intended use.

I Figures 1 through 4 show oneapparatus embodiment Main drive shaft 1carries frame 3 of this invention. suspended below support 2. A circularhole cut in this support permits the shaft to extend therethrough and besupported from above by bearings 11 and 12 and thrust bearing 13.Support legs 21 extend from the housing of bearing 13 to the uppersurface of the support. Near the upper end of the shaft 1 is thrustcollar 14 secured to the shaft by screw lock nut 15. Between bearings 11and 12 is a V-belt driving pulley'16 affixed to the shaft for belt drivefrom a suitably located motor (not shown).

' Below the support the shaft carries hub 18 pinned through the centerof the shaft toinsurerotation therewith. In

. a centrally located cylindrical bore of the shaft is tube 17 forguiding a strand to be processed. The tube extends beyond the upper endof the shaft through a hole in lock nut 15 to facilitate introduction ofthe strand- At the lowerend of the tube, which may conveniently be, ofceramic, metal, or the like, fitting 32 fastened in) a place by means ofset screw 34 leads the yarn into the bore of radial fitting ,36. Intothis radial opening is brought the end of a tube 35,'sucl1 as ofstainless steel, and this is held in place by means of a tight-fittingsleeve.

5 j and downward and then bends abruptly downward to useful according tothis invention. Figure 7 is a horizonterminate in an opening near thetop of screw-threaded The lower part of shaft 1 carries frame 3 by meansof bearings 44 and 46, which are in suitable housings constituting partof the suspended frame. This frame con-' sists of a number of'partswelded together. Cylin'drical member 4 is welded" to an upper plate 41'and a lower" plate 42, and conical stifiener 43 joins the lower platewith the housing for lower bearing 46. Tofurther support bearings 44 and46, cylindrical sleevelike member 48',

is welded to the outer part of their housingsa Cylindrical. member 47,only slightly larger in internal diameter tlian This tube extends moreor less radiallyjoutward the shaft at this point, floats between the twobearings, keeping them spaced apart, while Belleville spring 45 exertsan upward pressure against bearing 44 to relieve the end pressure onspacer sleeve 47.

The frame thus formed-supports a plurality ofcylindrical worm rolls 5,twelve being shown equally spaced around the periphery of theframeandgrooved ,or threaded alike. is press-fitted a gudgeon 51, whichextends through bearing 53 supported in suitable housings. tends throughand is keyed to Gilmeri pulley 55, which is toothed with a series oftransverse rectangular slots. The lower end of each worm roll issupported for rotation by a press-fitted insert 52 on bearing 54, whichiin turn is supported by a bent rod 56 welded to a plate 57 screwed tobottom plate 42 of the frame.

-To shaft 1 is keyed a fGilmer pulley 19 of the same peripheral size andsprocket pitch as pulleys 55. The twelve worm drive pulleys and thedriving pulley 19'are joined by a Gilmer timing belt 20 with the aid oftwo idler pulleys 61 and 62, which are smooth-surfaced for contact withthe back or smooth side of the timing belt. The belt passes outside eachworm drive pulley, back over an idler pulley about the drive pulley onthe shaft, against the other idler pulley, and onto the first worm drivepulley. The idler pulleys are mounted in the top plate. of the frame,which has been reinforced at these points,

by welding to the underside of the plate a substantial thickness ofmetal. The support for pulley 61 is shouldered bolt 63 threaded into oneof the reinforced Pulley 62 is mounted on adpulley carried thereby areheld in position by means of nut 67 threaded onto the upper end of thestud bolt. This arrangement for driving the worm rolls causes all ofthem to rotate once with each rotation of the shaft and the attachedguide.

During operation of the apparatus, the frame supporting the worms may beheld stationary or may be counterrotated by suitable snubber means toreduce the component of rotation of the strand about the axis of thehelix. Rotatable snubber roll 70, shown in Figure 5, accomplishes thisby bearing on the tips of some of the threads forming the surface of oneof the worms. Such a snubber roll is mounted on a suitable arm (notshown) which may depend from support 2., even as an extension of leg 21,if desired. While a lone snubber roll should be satisfactory, it may beconvenient to use two, three, or more. The roll, which should have aresilient surface, is so positioned as not to contact the yarn passingthereunder in the grooves of the worm. Figure 5A shows another snubbingarrangement, which utilizes belt 74 passing in non-slipping contact overpulleys 75, whose axes are parallel to the axes of the worm rolls.Arrows indicate the directions of rotation and suggest the relativespeeds of the belt and the rolls; contact of the belt with several ofthe rolls which have a considerably greater surface velocity in the samedirection, moves the entire group opposite to the individual wormrotation, the small resultant being indicated by the central arrow. Thisim-- posed counter-rotation can afford substantially completecancellation of the component of rotation that the apparatus otherwiseimparts to the strand being processed; a stationary belt actually wouldbring the component to a small negative value. For example, when thebelt is held stationary, the rotation of the Worm rollers against thebelt surface in a counter-clockwise direction will cause the rotatableframe to which the worm rollers are attached to rotate about its centralaxis in a clockwise direction. When the worm rollers are not rotatingand the belt is moved in a clock-wise direction, the rotatable framewill be driven in a counter-clockwise direction.

Into the upper end-ofeachworm. roll The gudgeon ex-,

When the belt is moved in a clockwise direction at the same surfacespeed as the rotating worm rollers rotating in a counter-clockwisedirection, the frame will be held stationary. When the belt is moving ina counter-clockwise direction, the rotatable frame will be driven in aclockwise direction. By controlling the direction and rate of rotationof the belt, the rotation of the frame and the configuration of theloops which fall from it may be controlled to any desirable'degree.Magnets may be used to prevent rotation also, as is'apparent withoutnecessity for illustration.

This apparatus calls for no unusual articles or construction materials.With the. exception of the drive belt, the entire apparatus may be steelor similar material. The guide for the strand, or portions of it, mayconsist of ceramic material. The various parts that are fastenedtogether may be joined by usual methods, such as welding, bolting, orriveting. The surface of the rolls may be blasted, pebbled, or slittedto aid in preventing wrap ping of a strand or parts thereof about theindividual rolls.

Details of operation of the apparatus just described follow. A strandend is introduced into the top of tube 17 and brought out at the lowerend of the tube. Depending upon the physical characteristics of thestrand, it may pass through the tube more easily by beingpushed manuallyat the entering end or merely by the pull of gravity, or the lower endof the tube may be connected temporarily to an evacuated line so thatthe flow of air into the top of the tube will carry the strand alongwith it. Similarly, the entrance of a sucker-gun apparatus such as thatof Miller Patent No. 2,667,964 may be juxtaposed to the bottom end ofthe tube for this purposeand then withdrawn with the strand travelingthrough itto continue with the stringing up. After securing the end ofthe strand from the exit of the tube, the person stringing up theapparatus then starts the motor to begin rotation of the guide and therolls. The guide passes about the group of worm rolls, paying off" thestrand about the outermost thirty degrees of each groove in-each roll isoccupied by the strand. Rotation of the rolls themselves also carriesthe strand around the group of rolls, a component of motion that may benullified in whole or part, as mentioned above. The configuration of thestrand as it falls after leaving the bottom of the worm rolls appears inFigure 1.

Assuming thirty inches as the diameter of the helix formed by the strandin passing from roll to roll, an operating speed of slightly over 2000rpm. draws the strand ofi from its source at a rate of about 5500 yardsper minute (neglecting rotation of the entire helical con figuration,which may be made nil if desired). When rotating at the above rate,rolls having a groove length of 6 inches for one complete turn (athread-root diameter of about 2 inches) impart a speed of about 330yards.

per minute to the strand, less than of its original rate of travel. Ifthe guide and the rolls rotate in the same direction, as shown, thedraw-0E speed of the strand is the difference of the two rates; it isthe sum of the two when these elements are counter-rotating. 'Thesmaller the roll diameter, the smaller the peripheral speed of thestrand, and the rolls may be tapered to reduced diameter at the bottomto reduce this speed component to the desired level. A residualrotational component favors maintenance of a circular shape to the loopsof the falling strand. The advancing of theyarn along the axis of thehelical configuration is a function'of the Pipheral speed and screwpitch of the rolls. With onekhalf inch pitch -to the grooves in theabove rolls, the rate. of advance is about 30 yards per minute or only afew thousandths of the supply speed of the strand. If the apparatus isan appreciable distance above thev collecting surface, the interveningfree fall of the strand may increase the impact somewhat, but thereduction from the supply rate will remain very substantial. 5

The orderly collection patterns that may be formed on a movingcollecting surface according to. this invention are highly desirable;the evenness of deposition ensures compactness of the pattern.Backwinding or withdrawal of the strand from the surface is much easierthan in conventional systems where the strand is allowed to fall atrandom with high impact speed and consequent frequent wedging of onelength of the strand among others or separation of the components of thestrand along portions of its length. Too, where the strandis to beprocessed further on the collecting surface, the regular configurationspermitted by this apparatusfacilitate uniformity. The collecting surfacemay be rotated, oscillated, or moved in a complex manner to provide thedesired pattern of collected strand. Simple rotation of the surfaceabout a center eccentric to that of the, apparatus permits buildup of atoroidal package ofthe strand. Two or more of these machines may, beoperated in juxta-.

position so as to interleave their respective strands as they fall onthe collecting surface, and other patterning arrangements will comereadily to mind.

Apparatus embodiments besides that just described also are useful inpracticing the process of this invention. Obviously, the number ofsupporting elements for the strand may be reduced (or increased) ortheir relative locations, sizes, or shapes varied, with attendant changein the shape of the strand configuration, at least two ele-. ments beingrequired for the desired processing of. the strand. Instead of producingsubstantially circular loops, such apparatus maybe designed to supplytriangular, square, semi-circular or other shapes of loops by omissionof some of the worm rolls or change in their locations. Reduction of therotational component about the axis of the configuration is desirable topreserve these loop shapes. Rhombic, or more elongated patterns, whichmay also be interleaved from a plurality of machines, are especiallyuseful when the, collected material: is to be processed into non-wovenarticles 'astaught by Lanterbach in patent application Serial No.312,067 filed Sep; tember 29, 1952, now abandoned.

Figure shows one such arrangement in plan. view,

render the rotational component nil. .If desired to,

including two identical two-roll modifications and 160 .of the apparatusof this invention suspended by suit-. able means (omitted from thedrawing forclarity) at-.. tached to supports 152 and 162 abovecollectingbelt 158 supported and moved by horizontal cylindrical rolls159 (of which only one is shown). Visible in the center of respectiveshafts 151 and 161 are bores intowhich strands 156 and 166,representedtherein as solid dots, are passing from suitable sources ofsupply not shown in the drawing. The first apparatus comprises verticalworm rolls 154 and 155 located upper right and lower leftfiwith respectto shaft 151. Tube 153, which extends to the left from the shaft, ishollow to receive the yarn from the bore to a line joining the roll axisand closed at each end by semi-circular arcs. From the bottom of therolls, the strand drops continuously in this elongated oval form ontothe belt moving underneath to the right. Resulting overlapping patternconfiguration 157 is clearly visible, between the two pieces ofapparatus, The structureof layers of strand may be deposited similarlyin crisscross fashion on top of those shown. Non-woven structures formedfrom batts so constructed are notable for their uniformity of strengthand other physical. characteristics in all azimuthal directions.

The screw type of advancing may be accomplished by having a minimum ofone threaded roll for the strand to move over in non-slipping contact,.the strand rolling orslipping sideways over the surface of the othersupporting elements, which may be smooth to facilitate the advancing.Alternatively, the element for advancing the strand may be threaded overonly part of its. surface, or otherwise fragmentary, instead ofcylindrical; this modification necessitates slipping contact of the.strand over the advancing element, while contact between the strand andat least one other supporting element should be nonslipping (althoughintermittent as the advancing element passes by). Such a movingadvancing element conveniently mayperform also the function of theguide. in encoiling the strand about a cylinder or other type ofsupporting element. a

, Movement of a supportlng element transverse tothev strand may replaceor supplement screw advancing, and

in simplest form such an element might constiti tean annular or toroidalsurface capable of continuous, ever; sion; of course, this surface, maybe fragmented also], as into a substantially parallel group of conveyerbelts clustered about a vertical axis. Gears or chains. could besubstituted for the belts, but in any event .the, outer or supportingsurface would move undirectionally to, ad-v vance the strand, the innersurface merely returning to the initialstrand-supporting position. Whenthis type of advancing and supporting element is used, the com pon'entof movement of the strand about the axis of the. helicalconfigurationdepends upon the relative orientation of the belts and the common axis,which if parallelwith the supporting elements fixed in azimuth--w.ould

promote circularity of the loops leaving the traveling belts, rotationofthe strand-supporting elements as a,

group about the central shaft may be attainedby a suitable planetarydrive, as by two sun sheaves or gears affixed respectively tothesupporting member through.

which the shaft passes and to the framework for the strand-supportingelements and interconnecting. planetary;- pulleys or gears revolvingabout the shaft. axis. in fixed: relationship to the rotating shaft.

Regardless of variations in kind or lojcationof strand-isupportingelements, theresulting configuration of strand so supported iscomprehended herein by'the general term helical, signifying primarilythe non-contiguous coiling of the strand about a rectilinear axisregardless of the.

cross section of the configuration perpendicular thereto and despiterotation or periodic change of orientation of and advancing of thestrand, as distinguished from systems where a coiled strand is merelyallowed to slip against an inscribed or a circumscribed surface orallowed to fall freely. The helical configuration here described has acontrolled extent and the strand describes an are substantially greaterthan a complete circle throughout that extent. In fact, strands of manysynthetic textile materials may be drawn to increased length by suitableorientation and shape of the rolls or other supporting elements when theconfiguration contains several complete turns of the supported strand.

Figure 6 and subsequent figures show a form of apparatus constructedaccording to this invention with the particular object of extending ordrawing a strand by means of worm rolls of substantially constantcross-section oriented outwardly from one another, i.e., splayed, in thedirection of advance. Drive shaft 81 is supported and driven insubstantially the same way as shaft 1 shown in earlier figures. Frame 89comprises top plate 77 supporting vertical angle irons 78, to the bottomof which is attached annular member 79. The upper part of the shaft hasa similar bore containing guide tube 82. Lower on the shaft is hollowfitting 83 connecting the vertical bore of the shaft to radial bore 84and held in place by a set screw. Around this part of the shaft andsecured to plate 85 is a collar having radial openings matching theradial bore 84 and the set-screw tapping. Also at ninety degrees tothese radial openings is a set-screw to secure the collar to the shaft.Sus pended from plate 85 and secured thereto are cylindrical shieldmembers 86. .Near the periphery of plate 85 is located guide 87, anddependent from the lower shield member 86 is guide 88.

Keyed to shaft 81 below top plate 85 is beveled drive gear 90 meshingwith each of five beveled driven gears 91, each driven gear beingfastened in turn to one of worm rolls 92. The gear arrangement, asviewed from above, appears in Figure 7. A hearing housing and supportfor the upper shaft bearing and for the five bearings of the worm rollsis support member 93, which is rigidly fastened to support sleeve 94 ofthe stationary frame. Relative positions of the upper ends of the wormrolls, the central drive shaft, and the auxiliary support pins 95 appearclearly in Figure 6. The pins are provided to make the path nearlycircular for the first few loops of the strand. The extensive supportsshown are necessary because the worm rolls splay out toward the bottomin order to provide the desired degree of drawing.

Sleeve 94 fastened to bottom plate 96 by welding to flanged lower shaftbearing-housing 97, which in turn is bolted to the bottom plate, isfurther supported by five evenly spaced plate braces 98 bolted to thebottom plate and to ribs aflixed to sleeve 94. This bracing ties thebottom plate rigidly to the sleeve, thus providing excellent anchoragein the bottom plate for supporting the lower ends of the worm rolls.Figure 9 is a detail of this superstructure. Suitably shaped angledsupports 99 bolted to the bottom plate carry two ball-bearing rollers100 on parallel axes for each worm roll, serving to support the lowerpart on a fixed axis of rotation. Similar supports 99' depending fromannular member 79 carry like rollers 100'.

The radial cross-section of each worm roll varies, tapering near the topto a smaller section that remains constant until near the. other end,where the roll decreases in radius. While an apex at the discharge endsof the worm rolls may be effective to slow or stop rotation of thestrand about the vertical axis, it also ensures no slippage back intothe drawing zone. The tapering at the upper end of the rolls is sodesigned as to permit several turns to be laid down on the worm rolls atconstant tension, preventing drawing or extension of the strand as well.as slippage between strand and rolls.' The taper angle. of the shoulderwith the parallel sides of the rolls approximates one half the angle bywhich the worm axis deviates from the vertical or central axis of theapparatus.

Generally, the construction should be rigid and precise in order to gainthe maximum benefits of smooth uniform operation. Greater or less drawis possible by increasing or decreasing the splay angle of the wormrolls or the over-all length of the rolls may be chosen to provide thedesired amount of draw, which for synthetic fibers often lies within therange of about three to six times the original length. This apparatuscan be strung up and operated similarly to the apparatus describedearlier, with the strand here passing also about the set of pins as wellas the rolls. The guide rotates counter to the direction of rotation ofthe rolls, as is apparent from the construction shown. The advantages ofthe apparatus shown and described above are combined in the apparatusjust considered plus the feature of extending the strand to increasedlength. The advantages of doing so are obvious.

Other shapes and orientations of worm rolls may be employed to draw astrand passing over them. Change in length of the strand is generally afunction of the inclination of the roll axes to the axis of the group,direction of rotation of the rolls as compared with that of the guide,and change in roll diameter from the. entering location of the strand tothe discharge location. Counterrotation of guide and rolls is favoredover rotation in the same direction because of the attendant increaseddraw. As noted above, no draw occurs in like apparatus whose rollelements are conical and are oriented with apex downward and axisinclined down and outward from the apex of the entire group if the apexangle (axial plane) of the element equals the angle of inclination ofthe element axis to the common axis; greater inclination of such anelement provides positive draw. Rolls may be made of varying section tovary initial and final draw rates, as well as total amount of draw. Thedrawing action may be spread over a considerable length of strand withexact control in location, a notable advantage over existing equipment.The drawn strand passing from apparatus of the type described may be fedto another similar apparatus for further drawing, and so on, in acascade arrangement. Additional ways of utilizing the apparatusconsidered here without departing from the invention will be evident.For example, the apparatus may be heated internally or externally andmay be wholly or partly enclosed, and the strand may be heatset by suchapparatus.

The claimed invention:

1. Novel process of delivering strand material in the form of loopscomprising the steps of initially directing the strand in asubstantially vertical downward direction, imparting to said strand ahelical configuration having an axis substantially parallel to theinitial direction of said strand, impelling the strand lengthwise ofitself to impart a component of movement thereto along its length whileadvancing it in the helical configuration, and releasing said strand atthe terminus thereof in the form of loops, said loops forming a helicalconfiguration, the strand retaining sufiicient component of movementthat the. helical configuration is retained as said strand falls underthe influence of gravity at a rate substantially less than the speed ofthe strand in its initial downward direction.

' 2. The process of claim 1 wherein the strand is positively supportedas the helical configuration is imparted and as the strand is impelledlengthwise while advancing it in the helical configuration.

3. The process of claim 1 wherein the rate of advance of the strand inthe helical configuration is less than ,1 of the rate of supply of thestrand.

4. The process of claim 1 in which the diameter of the helicalconfiguration varies in controlled manner with distance along the axisthereof.

5. The process of claim 1 in which the pitch of the helicalconfiguration is substantially fixed throughout and the strand isadvanced axially along the configuration to the terminus thereof.

6. Process of collecting the falling strand of claim g r therewith nearone end of the group of elements to receive the strand from a source ofsupply.

8. The apparatus of claim 7 in which an advancing element is threadedand is adapted to rotate on an axis substantially parallel to the axisof the helical configuration and fixed with respect thereto.

9. The apparatus of claim 7 adapted' for travel of the strand withrespect to the supporting elements, where- ,upon the respectivesupporting elements successively contact each portion of the strand.

10. The apparatus of claim 9 in which each of the supporting elements isalso a lengthwise advancing element.

11. The apparatus of claim 10 inwhich all of the supporting andadvancing elements are threaded externally and are adapted to rotate onaxes of their own fixed with respect to the axis of the helicalconfiguration.

12. The apparatus of claim 11 in which all the axes are parallel to oneanother.

13. The apparatus of claim 7 in combination with a collecting surfacemoving underneath, adapted to receive the strand as it is released fromthe apparatus in the form of loops.

14. The apparatus of claim 7 further comprising guide means forinitially directing the strand substantially parallel to the center ofrotation of the supporting element rotating in a circleperpendicular tothe helix axis.

.15. Apparatus comprising a plurality of similar helically groovedcylinders rotatable at the same rate and mounted on a rotatable frame,and guide means movable about the group of cylinders in synchronism withthe rotation of the cylinders so as to encoil a strand helically aboutthe plurality of cylinders for advancing in the grooves.

16. The apparatus of claim 15 in which shape and '18. Apparatuscomprising a plurality of similar helically grooved cylinders rotatableat the same rate and mounted on a rotatable frame, means to direct astrand in a substantially vertical direction into a tubular guide membermovable about the cylinders insynchronism with the rotation of thecylinders so as to encoil a strand helically about the cylinders andadvancing in the grooves, snubber means in bearing contact with at leastone of the cylinders to regulate the rotational component of theframe,'in combination with a collecting surface moving underneath tocollect the strand as it is released in loop form from the apparatus.

19. Apparatus comprising a plurality of yarn-process- I ing units, eachsaid unit comprising at least two similar helically grooved cylindersand guide means movable about the group of cylinders in synchronism withthe rotation of the cylinders to encoil a strand helically about I thecylinders for advancing in the grooves, said cylinders of each unitbeing rotatable at the same, rate and located with their axes parallelto each other and to a vertical axis of rotation of the guide means andat opposite sides thereof in a line perpendicular to the correspondingline of like units of apparatus immediately adjacent thereto; acollecting surface moving underneath said plurality of units in asubstantially horizontal plane and in a direction therein making anangle of' about forty-five degrees withsaid threaded element.

orientation of the cylinders are effective to extend a strand innon-slipping contact therewith as the cylinders rotate.

17. The apparatus of claim 16 in which the axes of the respectivecylinders are splayed outwardly in the direction of advance of a strandtherealong.

21. Apparatus comprising a plurality of elements mounted on a rotatableframe and grouped to support a strand making a circuit of the elementsin a substantially helical configuration having a substantially verticalaxis,

including a supporting guide means rotating in a circle perpendicular tothe helix axis concentric therewith nearone end of a group of elementsto receive the strand from a source of supply, and snubber means toregulate the component of rotation of the frame.

References Cited in the file of this patent UNITED STATES PATENTS1,960,743 Junkers May 29, 1934 2,424,490 Henry July 22, 1947 2,605,536Litzler Aug. 5, 1952 2,691,852 Slayter Oct. 19, 1954 2,742,737 McElroyApr. 24, 1956 FOREIGN PATENTS Great Britain Sept. 1, 1941

